Primula plant named ‘Kerbelbut’

ABSTRACT

A new and distinct cultivar of  Primula  plant named ‘Kerbelbut’, characterized by its upright, compact and uniform plant habit; large, double, fragrant and bright yellow-colored flowers that are held upright on strong and erect peduncles; large sepals that “frame” the flowers; freely flowering habit; and tolerance to low temperatures.

Botanical designation: Primula acaulis.

Cultivar denomination: ‘Kerbelbut’.

BACKGROUND OF THE INVENTION

The present Invention relates to a new and distinct cultivar of Primulaplant, botanically known as Primula acaulis, and hereinafter referred toby the cultivar name Kerbelbut.

The new Primula is a product of a planned breeding program conducted bythe Inventor in Over, Cambridge, United Kingdom. The objective of thebreeding program was to create new compact pot-type Primula cultivarswith numerous double flowers with short peduncles and attractive leafand flower coloration.

The new Primula originated from a cross-pollination made by theInventors in Over, Cambridge, United Kingdom of two unnamed proprietaryPrimula acaulis seedling selections, not patented, in March, 2001. Thenew Primula was discovered and selected by the Inventor as a floweringplant within the progeny of the stated cross-pollination in a controlledenvironment in Over, Cambridge, United Kingdom in February, 2002.

Asexual reproduction of the new cultivar by tissue culture since thesummer of 2002 in Enniscorthy, Ireland, has shown that the uniquefeatures of this new Primula are stable and reproduced true to type insuccessive generations.

SUMMARY OF THE INVENTION

Plants of the cultivar Kerbelbut have not been observed under allpossible environmental conditions. The phenotype may vary somewhat withvariations in environment such as temperature, light intensity,daylength, and fertility level without, however, any variance ingenotype.

The following traits have been repeatedly observed and are determined tobe the unique characteristics of ‘Kerbelbut’. These characteristics incombination distinguish ‘Kerbelbut’ as a new and distinct cultivar:

-   -   1. Upright, compact and uniform plant habit.    -   2. Large, double, fragrant and bright yellow-colored flowers        that are held upright on strong and erect peduncles.    -   3. Large sepals that “frame” the flowers.    -   4. Freely flowering habit.    -   5. Tolerant to low temperatures.

Plants of the new Primula differ from plants of the parent selections inthe following characteristics:

-   -   1. Plants of the new Primula are more compact than plants of the        parent selections.    -   2. Plants of the new Primula have double flowers whereas plants        of the parent selections have single flowers.    -   3. Plants of the Primula are sterile whereas plants of the        parent selections are fertile.

Plants of the new Primula can be compared to plants of the Primulaacaulis cultivar Val Horncastle, not patented. In side-by-sidecomparisons conducted in Over, Cambridge, United Kingdom, plants of thenew Primula differed from plants of the cultivar Val Horncastle in thefollowing characteristics:

-   -   1. Plants of the new Primula were more compact than plants of        the cultivar Val Horncastle.    -   2. Plants of the new Primula had smaller leaves than plants of        the cultivar Val Horncastle.    -   3. Plants of the new Primula had larger flowers than plants of        the cultivar Val Horncastle.    -   4. Plants of the new Primula had bright yellow-colored flowers        whereas plants of the cultivar Val Horncastle had pale        yellow-colored flowers.    -   5. Plants of the new Primula had larger sepals than plants of        the cultivar Val Horncastle.    -   6. Plants of the new Primula had strong upright peduncles        whereas plants of the cultivar Val Horncastle had weak arching        peduncles.

Plants of the new Primula can be compared to plants of the Primulaacaulis cultivar Sunshine Susie, not patented. In side-by-sidecomparisons conducted in Over, Cambridge, United Kingdom, plants of thenew Primula differed from plants of the cultivar Sunshine Susie in thefollowing characteristics:

-   -   1. Plants of the new Primula were more vigorous and stronger        than plants of the cultivar Sunshine Susie.    -   2. Plants of the new Primula had larger flowers than plants of        the cultivar Sunshine Susie.    -   3. Plants of the new Primula had larger sepals than plants of        the cultivar Sunshine Susie.    -   4. Plants of the new Primula flowered earlier than plants of the        cultivar Sunshine Susie.

BRIEF DESCRIPTION OF THE PHOTOGRAPHS

The accompanying colored photographs illustrate the overall appearanceof the new cultivar, showing the colors as true as it is reasonablypossible to obtain in colored reproductions of this type. Colors in thephotographs may differ slightly from the color values cited in thedetailed botanical description which more accurately describe the actualcolors of the new Primula.

The photograph on the first sheet comprises a side perspective view of atypical flowering plant of ‘Kerbelbut’ grown in a 11-cm container.

The photograph on the second sheet is a close-up view of a typicalflower of ‘Kerbelbut’.

DETAILED BOTANICAL DESCRIPTION

The aforementioned photographs, following observations and measurementsdescribe plants grown in Over, Cambridge, United Kingdom, in aglass-covered greenhouse and under commercial production practicesduring the spring. Plants were about four to five months old when thephotographs and description were taken. During the production of theplants, day temperatures ranged from 20 to 28° C. and night temperaturesranged from 15 to 20° C. In the following description, color referencesare made to The Royal Horticultural Society Colour Chart, 1995 Edition,except where general terms of ordinary dictionary significance are used.

-   Botanical classification: Primula acaulis cultivar Kerbelbut.-   Parentage:    -   -   Female, or seed, parent.—Unnamed proprietary Primula acaulis            seedling selection, not patented.        -   Male, or pollen, parent.—Unnamed proprietary Primula acaulis            seedling selection, not patented.-   Propagation:    -   -   Type.—By tissue culture.        -   Time to initiate roots.—About four weeks at 20° C.        -   Time to produce a rooted young plant.—About five weeks at            20° C.        -   Root description.—Fibrous; white in color.        -   Rooting habit.—Freely branching.-   Plant description:    -   -   Plant form/habit.—Upright, compact and uniform plant habit;            inverted triangle. Vigorous growth habit. Leaves basal.        -   Plant height.—About 10 to 16 cm.        -   Plant width (spread).—About 25 cm.        -   Foliage description.—Arrangement: Basal, simple. Length:            About 8 to 12 cm. Width: About 2.8 to 5.5 cm. Shape:            Oblanceolate. Apex: Obtuse. Base: Acute. Margin: Slightly            crenate; irregular; undulate. Texture, upper surface:            Slightly rugose; smooth. Texture, lower surface: Prominent            venation; pubescent. Venation pattern: Pinnate. Color:            Developing leaves, upper surface: 138A to 143B. Developing            leaves, lower surface: 146A to 146B. Fully expanded leaves,            upper surface: 137A to 144A. Fully expanded leaves, lower            surface: 137B to 144A. Venation, upper surface: 144A.            Venation, lower surface: 147C. Petiole length: About 1.5 to            2.2 cm. Petiole diameter: About 6 to 10 mm. Petiole texture,            upper and lower surfaces: Smooth, glabrous. Petiole color,            upper surface: 59B to 59C. Petiole color, lower surface:            59C.-   Flower description:    -   -   Flower type/habit.—Single, rounded double flowers; flowers            face upright and outward. Freely flowering habit with about            13 flower buds and flowers per plant.        -   Fragrance.—Moderately fragrant; typical of species.        -   Natural flowering season.—Recurrent flowering during the            spring in the United Kingdom. Flowers persistent.        -   Flower buds.—Height: About 8 to 11 mm. Diameter: About 5 to            8 mm. Shape: Ovoid. Color: 145A to 145D.        -   Flower diameter.—About 1.8 to 2.8 cm.        -   Flower depth.—About 1.2 to 1.9 cm.        -   Petals.—Quantity per flower: About 20 to 26 in several            concentric whorls. Length (including tube): About 7 to            13 mm. Width: About 9 to 16 mm. Shape: Obcordate. Apex:            Emarginate. Margin: Mostly entire. Texture, upper and lower            surfaces; Smooth, glabrous; satiny. Color: Developing            petals, upper surface: 3A to 3B. Developing petals, lower            surface: 3C to 3D. Fully expanded petals, upper surface: 9A            to 9C; color becoming closer to 14A to 2B with development.            Fully expanded petals, lower surface: 2A to 2B.        -   Sepals.—Quantity per flower: Typically four or five in a            single whorl, fused at the base; sepals are large and            “frame” the flower. Length: About 1.7 to 3 cm. Width: About            1 to 2.5 cm. Shape: Rounded to oblong. Apex: Obtuse.            Texture, upper and lower surfaces: Smooth, glabrous; rugose.            Color, upper surface: 137A to 137B. Color, lower surface:            138A to 138B.        -   Peduncles.—Length: About 4.5 to 8.5 cm. Diameter: About 2 to            3 mm. Orientation: Mostly erect. Strength: Strong. Texture:            Pubescent. Color: 60C to 60D.        -   Reproductive organs.—Development of reproductive organs has            not been observed.-   Disease/pest resistance: Plants of the new Primula have not been    noted to be resistant to pathogens and pests common to Primula.-   Temperature tolerance: Plants of the new Primula have been observed    to have tolerate temperatures from about −5 to 28° C.

1. A new and distinct cultivar of Primula plant named ‘Kerbelbut’, asillustrated and described.